Transducer/Waveguide Engagement Mechanisms for Ultrasonic Surgical Instruments

ABSTRACT

An ultrasonic surgical instrument includes a transducer assembly having a distal engagement member and configured to supply ultrasonic energy. A waveguide defines a longitudinal axis and has a proximal engagement member configured to threadingly engage the distal engagement member. The waveguide is configured to transmit the ultrasonic energy therealong to a distal end thereof for treating tissue. A torque member is coupled to the transducer assembly and is disposed about the longitudinal axis. The torque member is selectively rotatable about the longitudinal axis and relative to the waveguide to threadingly engage the transducer assembly and the waveguide to one another. The torque member includes a plurality of fingers pivotably coupled thereto and movable between a closed position and an open position. In the open position, each finger extends substantially perpendicularly from the longitudinal axis to define a moment arm that facilitates the engagement of the transducer assembly and the waveguide.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments and, moreparticularly, to ultrasonic surgical instruments for grasping andtreating tissue.

2. Background of Related Art

Ultrasonic surgical instruments utilize ultrasonic energy, i.e.,ultrasonic vibrations, to treat tissue. More specifically, ultrasonicsurgical instruments utilize mechanical vibration energy transmitted atultrasonic frequencies to coagulate, cauterize, fuse, seal, cut,desiccate, and/or fulgurate tissue to effect hemostasis.

Endoscopic ultrasonic instruments transmit ultrasonic energy produced bya generator and transducer assembly along a waveguide to an end effectorassembly that is spaced-apart from the generator and transducerassembly. Thus, the end effector assembly may be positioned within aninternal surgical site, e.g., inserted through a cannula assembly, whilethe generator and transducer assembly remains externally disposed, inorder to perform so-called “minimally-invasive” surgical procedures.

Some endoscopic ultrasonic instruments include a portable generator andtransducer assembly engaged on the instrument itself. Such instrumentsgenerally include an elongated waveguide interconnecting the generatorand transducer assembly and the end effector assembly. Typically, thegenerator and transducer assembly is configured as a reusable componentthat is releasably engagable with the instrument and waveguide, e.g., topermit use of the generator and transducer assembly with disposablecomponents and/or to facilitate sterilization of other reusablecomponents in preparation for reuse. As such, in preparation forsubsequent use, the generator and transducer assembly is disengaged fromthe used waveguide and is engaged to a new, or sterilized waveguide.However, during each assembly, it is important to ensure that thewaveguide and generator and transducer assembly are sufficiently securedto one another to maintain the engagement therebetween during use and toensure proper operation thereof.

SUMMARY

As used herein, the term “distal” refers to the portion that is beingdescribed which is further from a user, while the term “proximal” refersto the portion that is being described which is closer to a user.

Any or all of the aspects described herein, to the extent they areconsistent, may be used in conjunction with any of the other aspectsdescribed herein.

In accordance with the present disclosure, an ultrasonic surgicalinstrument is provided. The ultrasonic surgical instrument generallyincludes a transducer assembly, a waveguide, and a torque member. Thetransducer assembly is configured to supply ultrasonic energy andincludes a distal engagement member. The waveguide defines alongitudinal axis and has a proximal engagement member that isconfigured to threadingly engage the distal engagement member of thetransducer assembly. The waveguide is configured to transmit theultrasonic energy from the transducer assembly from the proximalengagement member, along the waveguide, and to a distal end thereof fortreating tissue. The torque member is coupled to the transducer assemblyand is disposed about the longitudinal axis. The torque member isselectively rotatable about the longitudinal axis and relative to thewaveguide to threadingly engage the transducer assembly and thewaveguide to one another, e.g., to rotate the transducer assembly intoengagement with the waveguide. The torque member includes a plurality offingers pivotably coupled thereto and movable between a closed positionand an open position. In the closed position, the fingers are disposedin close proximity to one another and relative to the longitudinal axis.In the open position, each finger extends radially-outwardly from thelongitudinal axis in substantially perpendicular orientation relative tothe longitudinal axis to define a moment arm configured to facilitatethreading engagement of the transducer assembly and the waveguide to oneanother.

In one aspect, the ultrasonic surgical instrument further includes atool assembly disposed at the distal end of the waveguide. The toolassembly includes a blade that is coupled (or formed with) the waveguideand a clamp member that is movable relative to the blade from an openposition to a clamped position for clamping tissue between the clampmember and the blade.

In another aspect, a transducer and generator assembly is provided. Thetransducer and generator assembly incorporates the transducer assemblyand a generator that is coupled to the transducer assembly. Thetransducer and generator assembly may be configured to rotatably supportthe transducer assembly thereon to facilitate engagement of thetransducer assembly and waveguide to one another. Further, thetransducer and generator assembly may be releasably engagable with ahandle assembly of the ultrasonic surgical instrument.

In yet another aspect, the proximal engagement member of the waveguideincludes a threaded extension. The threaded extension is configured forengagement within a threaded bore defined within the distal engagementmember of the transducer assembly.

In still another aspect, the fingers of the torque member are stable, orat-rest in each of the open and closed positions. Further, the fingersmay be biased towards the open and/or the closed position.

Another ultrasonic surgical instrument provided in accordance with thepresent disclosure includes a transducer assembly, a waveguide, and alatch mechanism. The transducer assembly is configured to supplyultrasonic energy and includes a distal engagement member. The waveguidedefines a longitudinal axis and includes a proximal engagement memberthat is configured to engage the distal engagement member of thetransducer assembly. The waveguide is configured to transmit theultrasonic energy from the transducer along the waveguide to a distalend thereof for treating tissue. The latch mechanism is configured toreleasably engage the transducer assembly and the waveguide to oneanother. More specifically, the latch mechanism includes a crank armhaving a first end and a second end. The crank arm is pivotably coupledto one of the transducer assembly and the waveguide at the first endthereof via a first pivot. A linkage is pivotably coupled to the secondend of the crank arm at a first end of the linkage via a second pivot. Asleeve member is pivotably coupled to the linkage at a second end of thelinkage via a third pivot. The sleeve member is partially, or entirely,positionable about the other of the transducer assembly and thewaveguide. The crank arm is selectively pivotably about the first pivotbetween an unlocked position and a locked position. In the unlockedposition, the distal engagement member of the transducer assembly andthe proximal engagement member of the waveguide are spaced-apartrelative to one another, i.e., the transducer assembly and waveguide aredisengaged from one another. In the locked position, the first andsecond pivots are aligned with one another and the longitudinal axis.Further, in the locked position, the third pivot is disposed in anover-center position relative to the first and second pivots and thelongitudinal axis such that the sleeve member maintains the distalengagement member of the transducer assembly and the proximal engagementmember of the waveguide in engagement with one another.

In one aspect, the crank arm is pivotably coupled to the transducerassembly at the first end thereof and the waveguide is insertablethrough a lumen defined through the sleeve member. In such an aspect,the waveguide may include a proximal collar that is inhibited frompassing through the sleeve member. As such, in the locked position, thesleeve member abuts the proximal collar to maintain the distalengagement member of the transducer assembly and the proximal engagementmember of the waveguide in engagement with one another. Further, thelatch mechanism may be configured such that, in the locked position, theproximal engagement member of the waveguide and the distal engagementmember of the transducer assembly engage one another at a displacementnode.

In another aspect, the crank arm is pivotably coupled to the waveguideat the first end thereof and the sleeve member is positionable about aportion of the transducer assembly. In such an aspect, the transducerassembly may include a distal collar such that, in the locked position,the sleeve member abuts the distal collar to maintain the distalengagement member of the transducer assembly and the proximal engagementmember of the waveguide in engagement with one another. Further, thelatch mechanism may be configured such that, in the locked position, theproximal engagement member of the waveguide and the distal engagementmember of the transducer assembly engage one another at a displacementanti-node and/or such that a pivot point between the crank arm and thewaveguide is located at a displacement node.

In yet another aspect, a tool assembly is disposed at the distal end ofthe waveguide. The tool assembly includes a blade coupled to (or formedwith) the waveguide and a clamp member movable relative to the bladefrom an open position to a clamped position for clamping tissue betweenthe clamp member and the blade.

In still another aspect, the ultrasonic surgical instrument includes atransducer and generator assembly that incorporates the transducerassembly and a generator coupled to the transducer assembly. Thetransducer and generator assembly may be releasably engagable with ahandle assembly of the ultrasonic surgical instrument.

In accordance with the present disclosure, another ultrasonic surgicalinstrument including a transducer assembly, a waveguide, and a latchmechanism is provided. The transducer assembly is configured to supplyultrasonic energy and includes a distal stop member disposed at a distalend thereof. The waveguide includes a proximal hub. The waveguide alsodefines a longitudinal recess configured to receive at least a portionof the transducer assembly therein and a transverse lumen extendingtherethrough in substantially parallel orientation relative to thelongitudinal recess. The waveguide is configured to transmit theultrasonic energy from the transducer assembly along the waveguide to adistal end thereof for treating tissue. The latch mechanism isconfigured to releasably engage the transducer assembly and thewaveguide to one another. More specifically, the latch mechanismincludes an angled chuck movably disposed within the transverse lumen ofthe waveguide. The angled chuck defines an angled, or taperedconfiguration having a first end defining a first width and a second enddefining a second width that is smaller than the first width. The angledchuck also includes a pair of spaced-apart legs at the second endthereof that define a slot therebetween. The legs are angled relative toone another such that the legs define a first gap distance at a closedend thereof and a second gap distance at an open end thereof that isgreater than the first gap distance. The angled chuck is selectivelymovable between an unlocked position and a locked position. In theunlocked position, insertion of the transducer assembly into thelongitudinal recess and through the slot is permitted. Likewise, removalof the transducer assembly from the longitudinal recess and slot ispermitted in the unlocked position. In the locked position, on the otherhand, withdrawal of the distal stop member of the transducer assemblythrough the slot is inhibited. Further, in this locked position, theangled chuck is wedged between the distal stop member of the transducerassembly and the proximal hub of the waveguide to engage the transducerassembly and waveguide to one another.

In one aspect, the latch mechanism further includes a lock pusher thatis positioned adjacent the first end of the chuck. The lock pusher isselectively depressible to move the chuck from the unlocked position tothe locked position. The latch mechanism may also include an unlockpusher that is positioned adjacent the second end of the chuck. Theunlock pusher is selectively depressible to move the chuck from thelocked position to the unlocked position.

In another aspect, a tool assembly is provided. The tool assembly isdisposed at the distal end of the waveguide and includes a blade and aclamp member. The blade is coupled to (or formed with) the waveguide andthe clamp member is movable relative to the blade from an open positionto a clamped position for clamping tissue between the clamp member andthe blade.

In still another aspect, the angled chuck, in the locked position, maybe located at a displacement anti-node.

Another ultrasonic surgical instrument provided in accordance with thepresent disclosure includes a transducer assembly, a waveguide, and alatch mechanism. The transducer assembly is configured to supplyultrasonic energy and includes a distal engagement member. Thetransducer assembly further includes a pair of opposed knobs extendingoutwardly therefrom adjacent a distal end thereof. The waveguide has aproximal engagement member that is configured to engage the distalengagement member of the transducer assembly. The waveguide isconfigured to transmit the ultrasonic energy from the transducer alongthe waveguide from the proximal engagement member to a distal endthereof for treating tissue. The latch mechanism is configured toreleasably engage the transducer assembly and the waveguide to oneanother. The latch mechanism includes a lever including a handleportion, an intermediate portion, and an engaging portion. The lever ispivotably coupled to the waveguide about the intermediate portionthereof. The handle portion extends from one end of the intermediateportion, while the engaging portion extends from the other end of theintermediate portion. The engaging portion defines a bifurcatedconfiguration and includes a pair of hook members. The handle portion isselectively movable between an unlocked position and a locked positionto move the hook members into engagement with the knobs of thetransducer assembly to engage the distal engagement member of thetransducer assembly and the proximal engagement member of the waveguidewith one another.

In one aspect, the proximal engagement member of the waveguide and thedistal engagement member of the transducer assembly are configured toengage one another at a displacement anti-node. Further, the pivot pointbetween the lever and the waveguide may be located at a displacementnode.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects and features of the present disclosure willbecome more apparent in light of the following detailed description whentaken in conjunction with the accompanying drawings wherein likereference numerals identify similar or identical elements:

FIG. 1 is a side, perspective view of an ultrasonic instrument providedin accordance with the present disclosure;

FIG. 2 is an enlarged, side, perspective view of the area of detailindicated in FIG. 1;

FIG. 3 is a side, perspective view of the ultrasonic instrument of FIG.1 showing a transducer and generator assembly (“TAG”) disengagedtherefrom;

FIG. 4 is an enlarged, side, perspective view of a waveguide assembly ofthe ultrasonic instrument of FIG. 1;

FIG. 5 is an enlarged, side, perspective view of the TAG of theultrasonic instrument of FIG. 1;

FIG. 6A is a perspective view of a torque member configured for use withthe ultrasonic instrument of FIG. 1, wherein the torque member is in aclosed position;

FIG. 6B is a perspective view of the torque member of FIG. 6A shown inan open position;

FIG. 7 is an end view of another torque member configured for use withthe ultrasonic instrument of FIG. 1, shown in the open position;

FIG. 8 is an end view of yet another torque member configured for usewith the ultrasonic instrument of FIG. 1, shown in the open position;

FIG. 9 is a perspective view of another ultrasonic instrument providedin accordance with the present disclosure, shown with parts separated;

FIG. 10A is a side view of a waveguide, TAG, and latch mechanismconfigured for use with the ultrasonic instrument of FIG. 9, wherein thewaveguide and TAG are disengaged from one another;

FIG. 10B is a side view of the waveguide, TAG, and latch mechanism ofFIG. 10A during engagement of the waveguide and TAG to one another;

FIG. 10C is a side view of the waveguide, TAG, and latch mechanism ofFIG. 10A, wherein the waveguide and TAG are engaged to one another;

FIG. 11 is a side, cross-sectional view of the ultrasonic instrument ofFIG. 9 in a fully assembled condition using the latch mechanism of FIG.10A;

FIG. 12A is a side view of another waveguide, TAG, and latch mechanism,wherein the waveguide and TAG are disengaged from one another;

FIG. 12B is a side view of the waveguide, TAG, and latch mechanism ofFIG. 12A, wherein the waveguide and TAG are engaged to one another;

FIG. 13 is a perspective view of a cuff of the latch mechanism of FIG.12A;

FIG. 14 is a side, cross-sectional view of an ultrasonic instrumentincorporating the waveguide, TAG, and latch mechanism of FIG. 12A in afully assembled condition;

FIG. 15 is a side, cross-sectional view of another ultrasonic instrumentprovided in accordance with the present disclosure, wherein the TAG isdisengaged from the waveguide;

FIG. 16 is a side, cross-sectional view of the ultrasonic instrument ofFIG. 15, wherein the TAG is engaged to the waveguide;

FIG. 17A is a longitudinal, cross-sectional view of another latchmechanism for an ultrasonic instrument, wherein the latch mechanism isdisposed in an unlocked position;

FIG. 17B is a transverse, cross-sectional view of the latch mechanism ofFIG. 17A in the unlocked position;

FIG. 18A is a longitudinal, cross-sectional view of the latch mechanismof FIG. 17A, wherein the latch mechanism is disposed in a lockedposition; and

FIG. 18B is a transverse, cross-sectional view of the latch mechanism ofFIG. 18A in the locked position.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, one embodiment of an ultrasonic instrumentexemplifying the features of the present disclosure is shown generallyidentified by reference numeral 10. Ultrasonic instrument 10 includes ahandle assembly 12, a shaft 14, and a tool assembly 16. Handle assembly12 supports a battery assembly 18 and an ultrasonic transducer andgenerator assembly (“TAG”) 20, and includes a rotatable collar 22, anactivation button 24, and a clamp trigger 26. Battery assembly 18 andTAG 20 are each releasably secured to a body portion 28 of handleassembly 12, and are removable from body portion 28 to facilitatedisposal of ultrasonic instrument 10, with the exception of batteryassembly 18 and TAG 20, or to facilitate sterilization of some or all ofthe components of ultrasonic instrument 10.

With reference to FIGS. 1-3, shaft 14 defines a longitudinal axis “X-X”and includes a waveguide 30 which extends through shaft 14 from handleassembly 12 to tool assembly 16. A distal end of the waveguide 30defines a blade 32. A proximal end of the waveguide 30 is configured toengage TAG 20. Waveguide 30, as will be described in greater detailbelow, is configured to transmit ultrasonic energy produced by TAG 20along waveguide 30 to blade 32 for treating tissue.

Body portion 28 of handle assembly 12 defines a recess 250 therein thatis configured to receive TAG 20 therein. TAG 20 is removably engagablewithin recess 250 of body portion 28, e.g., via snap-fit engagement.When engaged within recess 250, TAG 20 is electrically coupled tobattery assembly 18, permitting battery assembly 18 to supply power toTAG 20. Further, TAG 20 is operably engagable with waveguide 30, as willbe described in greater detail below, thus allowing the ultrasonicenergy produced by TAG 20 to be transmitted along waveguide 30 to blade32 for treating tissue.

Tool assembly 16, as best shown in FIG. 2, includes a clamp member 58that is pivotable relative to blade 32 between an open position and aclamping position for grasping tissue therebetween. The clamp member 58is moved from the open position to the clamping position in response toactuation of the clamp trigger 26, as will be described in greaterdetail below.

Continuing with reference to FIGS. 1-3, clamp trigger 26 of handleassembly 12 cooperates with a drive assembly (not shown) to transitionclamp member 58 from the open position to the clamping position upondepression, or squeezing of clamp trigger 26 towards battery assembly18. Activation button 24 extends distally from handle assembly 12adjacent clamp trigger 26. Activation button 24 is configured toselectively activate battery assembly 18 and TAG 20 to supply ultrasonicenergy to tool assembly 16 in two power settings, e.g., a high powermode and a low power mode, although other configurations are alsocontemplated. Rotatable collar 22 is rotatable in either direction aboutlongitudinal axis “X-X” to rotate tool assembly 16 about longitudinalaxis “X-X” to better position tool assembly 16 for clamping and treatingtissue.

In preparation for use, battery assembly 18 is engaged to handleassembly 12 and TAG 20 is engaged within recess 250 of body portion 28of handle assembly 12. TAG 20 is also engaged to waveguide 30 and iselectrically coupled to battery assembly 18, either simultaneously withthe engagement of TAG 20 within recess 250 of body portion 28, orindependently thereof.

With ultrasonic instrument 10 in the assembled condition, ultrasonicinstrument 10 is advanced into the surgical site and manipulated suchthat tool assembly 16 is positioned with tissue to be treated disposedbetween clamp member 58 and blade 32 thereof. Thereafter, clamp trigger26 is depressed, or squeezed towards battery assembly 18 to transitionclamp member 58 to the clamping position to clamp tissue between clampmember 58 and blade 32. Blade 32 may then be activated, e.g., activationbutton 24 may be depressed, to supply ultrasonic energy from TAG 20,along waveguide 30, to blade 32. Ultimately, the ultrasonic energyprovided at blade 32 is used to seal or otherwise treat tissue clampedbetween clamp member 58 and blade 32.

As can be appreciated, in order to properly control the ultrasonicenergy provided at blade 32, to ensure proper functionality, and tomaintain the engagement between waveguide 30 and TAG 20 during use, itis important to ensure that waveguide 30 and TAG 20 are properly andsufficiently secured to one another. In particular, it is important toensure proper transmission of the standing ultrasonic wave from TAG 20to and along waveguide 30. Further, since waveguide 30 and/or TAG 20 arereleasably engagable with one another (and with handle assembly 12), itis important to provide an engagement configuration that is consistentlyrepeatable for each subsequent engagement of TAG 20 and waveguide 30 tohelp ensure an effective engagement each time TAG 20 and waveguide 30are engaged to one another.

Turning now to FIGS. 4-5, in some embodiments, waveguide 30 includes athreaded extension 34 extending from proximal portion 33 thereof forengaging TAG 20 thereon. Threaded extension 34 is configured forthreading engagement within threaded bore 266 of horn 264 of TAG 20.More specifically, TAG 20 has a body portion 254 that includes an upperportion 256 supporting the generator components (not explicitly shown)of TAG 20. A cover 268 is supported on body portion 254 of TAG 20 toenclose the generator components (not explicitly shown) of TAG 20. Bodyportion 254 of TAG 20 further includes a pair of support members 258,260 that extend beneath upper portion 256 and define cradles thatrotatably support spinner assembly 252. Spinner assembly 252 includesthe components of transducer assembly 253 of TAG 20, includingdistally-extending horn 264. Horn 264, as mentioned above, includesthreaded bore 266 defined therein at the distal end thereof and isconfigured to threadably engage threaded extension 34 of waveguide 30.Spinner assembly 252 extends through the proximal end of body portion254 and includes a torque member 300 extending proximally from TAG 20.As will be described below, torque member 300 is transitionable from aclosed position to an open position to facilitate rotation of spinnerassembly 252 to threadingly engage transducer assembly 253 and waveguide30 to one another.

Referring now to FIGS. 1-5 and 6A-6B, torque member 300, as mentionedabove, extends proximally from TAG 20 and is transitionable from theclosed position (FIG. 6A) to the open position (FIG. 6B) to facilitateengagement of transducer assembly 253 and waveguide 30 to one another.More specifically, torque member 300 includes a distal shaft 310 that isfixedly engaged to, monolithically formed with, or otherwise coupled tospinner assembly 252 at the distal end of distal shaft 310. Whenultrasonic instrument 10 is fully assembled, torque member 300 andspinner assembly 252 are aligned with waveguide 30 to define a commonlongitudinal axis “X-X.” Torque member 300 further includes a proximalportion 320 having plurality of proximal fingers 322 that are pivotablycoupled to distal shaft 310 at the proximal end of distal shaft 310.Proximal fingers 322 of proximal portion 320 are moveable between theclosed position (FIG. 6A), wherein proximal fingers 322 are disposed inclose proximity to one another and to longitudinal axis “X-X” such thatproximal portion 320 defines a generally cylindrical configurationcentered about longitudinal axis “X-X,” and the open position (FIG. 6B),wherein proximal fingers 322 are flared radially outwardly insubstantially transverse orientation relative to longitudinal axis “X-X”such that each proximal finger 322 defines a moment arm to facilitateengagement of transducer assembly 253 and waveguide 30 to one another,as will be described below.

As shown in FIG. 6A, torque member 300 includes a pair of opposedproximal fingers 322 that each define approximately one-half of thegenerally cylindrical configuration of torque member 300 when torquemember 300 is disposed in the closed position (FIG. 6A). Each proximalfinger 322 is pinned to distal shaft 310 via a pivot pin 324, althoughother pivot or hinge mechanisms (not shown) may also be provided. Pivotpins 324 extend substantially-transversely relative to longitudinal axis“X-X” such that proximal fingers 322 are pivotable about pivot pins 324and relative to distal shaft 310 from the closed position (FIG. 6A) tothe open position (FIG. 6B). Further, pivot pins 324 may each include atorsion spring (not shown) disposed thereabout, or any other suitablebiasing member may be provided, for biasing proximal fingers 322 towardthe closed position (or the open position).

In order to transition proximal fingers 322 from the closed position tothe open position, proximal fingers 322 are grasped and pivoted awayfrom one another toward the open position (against the bias, inembodiment where proximal fingers 322 are biased towards the closedposition). Proximal fingers 322 may be configured to snap or click outof the closed position and/or into the open position upon sufficientpivoting of proximal fingers 322 towards the open (or closed) position.As best shown in FIG. 6B, each proximal finger includes a tab 326 havingfirst and second surfaces 327, 329 disposed in perpendicular orientationrelative to one another. Distal shaft 310 includes a pair of slots 312defined therein, each slot 312 defining a base surface 314 andconfigured to receive one of the tabs 326 therein. Tabs 326 arerotatable within slots 312 as proximal fingers 322 are moved between theopen and closed positions. More specifically, in the closed position,first surfaces 327 of tabs 326 are substantially parallel relative toand mating with base surfaces 314 of slots 312, while in the openposition, second surfaces 329 of tabs 326 are substantially parallel toand mating with base surfaces 314 of slots 312. This configuration,wherein second surfaces 329 of tabs 326 are substantially parallel andmating with base surfaces 314 of slots 312 in the open position, helpsto ensure that proximal fingers 322 are disposed in substantiallytransverse orientation relative to longitudinal axis “X-X” of distalshaft 310 when in the open position, thus achieving the greatestpossible moment arm to facilitate engagement of transducer assembly 253of TAG 20 and waveguide assembly 30 to one another, as will be describedbelow. Further, tabs 326 may be formed at least partially from aresilient material such that tabs 326 are resiliently deformed to permittransitioning of proximal fingers 322 from the closed position towardsthe open position and from the open position towards the closedposition, i.e., such that tabs 326 are deformed when proximal fingers322 are disposed intermediately of the open and closed positions. Assuch, tabs 326 may be configured to snap or click into the closedposition, e.g., whereby tabs 326 are resiliently returned to the initialposition once first surfaces 327 are mating with base surface 314,and/or the open position, e.g., whereby tabs 326 are resilientlyreturned to the initial position once second surfaces 329 mate with basesurface 327. In other words, this configuration corresponds to abi-stable configuration of fingers 322, wherein fingers 322 are at-rest,or stable in both the open and closed positions, and are biased from theintermediate position (towards either or both of the open and closedpositions). Any other suitable mechanism for retaining proximal fingers322 in either or both of the open and closed positions may also beprovided, e.g., ratchet mechanisms, snap-fit engagements, etc. Further,mechanisms for automatically deploying and/or returning proximal fingers322 to/from the open and closed positions may also be provided.

Referring to FIGS. 7-8, various other embodiments of torque members300′, 300″ similar to torque member 300 (FIGS. 6A-6B) are shown. Torquemember 300′, shown in FIG. 7, includes three equally-spaced proximalfingers 322′ pivotably coupled to distal shaft 310′ and movable relativethereto between closed and open positions, while torque member 300″,shown in FIG. 8, includes four equally-spaced proximal fingers 322″pivotably coupled to distal shaft 310″ and moveable relative theretobetween closed and open positions. Torque members 300′, 300″ areotherwise similar to and may include any of the features of torquemember 30 (FIGS. 6A-6B). In fact, any number of proximal flanges and/orany configuration thereof may be provided as desired, to facilitategrasping and rotating the torque member in order to secure transducerassembly 253 of TAG 20 and waveguide 30 (see FIG. 3) to one another.

Referring again to FIGS. 1-5 and 6A-6B, in order to assemble ultrasonicinstrument 10 for use, battery assembly 18 is engaged to handle assembly12 and TAG 20 is engaged within recess 250 of body portion 28 of handleassembly 12. With TAG 20 engaged within recess 250, transducer assembly253 of TAG 30 may then be secured to waveguide 30. More specifically, inorder to secure transducer assembly 253 to waveguide 30, proximalportion 320 of torque member 300 is transitioned from the closedposition (FIG. 6A) to the open position (FIG. 6B) such that proximalfingers 322 are disposed in substantially transverse, or perpendicularorientation relative to longitudinal axis “X-X.” In this position,proximal fingers 322 not only provide a more-ergonomic configuration forgrasping torque member 300, but also act as moment arms to facilitaterotation of torque member 300 with minimized force requirements, thus,facilitating the engagement of threaded bore 266 of horn 264 oftransducer assembly 253 and threaded extension 34 of waveguide 30 tothreadingly engage waveguide 30 and transducer assembly 253 of TAG 20 toone another. That is, with proximal fingers 322 extending radiallyoutwardly from longitudinal axis “X-X” to define moment arms, relativelyless rotational force is required to sufficiently engage threadedextension 34 within threaded bore 266. As can be appreciated, the lengthof proximal fingers 322 may be selected in accordance with the necessaryengagement between threaded extension 34 and threaded bore 266. Forexample, where a relatively stronger engagement is required, proximalfingers 322 may define increased lengths, thus defining greater momentarms and reducing the amount of rotational force necessary tosufficiently engage transducer assembly 253 and waveguide 30 to oneanother.

Once transducer assembly 253 and waveguide 30 are sufficiently engagedto one another, proximal portion 320 of torque member 300 is returned tothe closed position, wherein proximal fingers 322 are disposed in closeproximity to one another and relative to longitudinal axis “X-X.” Thisconfiguration inhibits torque member 300 from catching, snaring, orotherwise interfering with the manipulation and/or use of ultrasonicinstrument 10.

With transducer assembly 253 and waveguide 30 secured to one another,ultrasonic instrument 10 may be utilized, as mentioned above, to performone or more surgical procedures. At the completion of the surgicalprocedure(s), torque member 300 may once again be transitioned to theopen position to facilitate disengagement of transducer assembly 253 andwaveguide 30, e.g., via rotating torque member 300, such that,ultimately, TAG 20 may be disengaged from handle assembly 12 fordisposing of the disposable components of ultrasonic instrument 10and/or to facilitate sterilization of the reusable components inpreparation for reuse.

With reference now to FIG. 9, another embodiment of an ultrasonicinstrument is shown generally identified by reference numeral 400.Ultrasonic instrument 400 is similar to ultrasonic instrument 10 (FIGS.1-3) and, thus, only the differences therebetween will be described indetail hereinbelow, while discussion of similar components will bebriefly summarized or omitted entirely.

Ultrasonic instrument 400 generally includes a handle assembly 412, ashaft 414, and a tool assembly (not shown) that is similar to toolassembly 16 (FIG. 2). Handle assembly 412 supports a battery assembly418 and a TAG 420. A waveguide 430 extends through shaft 414 from handleassembly 412 to the tool assembly (see FIG. 2). Waveguide 430 isconfigured to transmit ultrasonic energy produced by TAG 420 alongwaveguide 430 to the tool assembly (see FIG. 2) for treating tissue.Battery assembly 418 and TAG 420 are releasably engagable with bodyportion 428 of handle assembly 412, while waveguide 430 is releasablyengagable with TAG 420.

Continuing with reference to FIG. 9, TAG 420 includes an upper portion456 supporting the generator components (not explicitly shown) thereofand a lower portion 458 that supports the components of transducerassembly 453. Handle assembly 412 defines a recess 450 therein that isconfigured to receive TAG 420 therein, e.g., in snap-fit or othersuitable engagement therewith. Recess 450 defines an open proximal endconfigured to receive tapered proximal portion 432 of waveguide 430 suchthat tapered proximal portion 432 of waveguide 430 and transducerassembly 453 of TAG 420 may be engaged to one another. Moreparticularly, tapered proximal portion 432 of waveguide 430 includesproximal collar 434 and a recess 436 defined therein and extendinginwardly from proximal surface 438 of proximal collar 434. Recess 436 isconfigured to receive horn 464 of transducer assembly 453 of TAG 420therein. Horn 464 may be configured for friction-fit (or other suitableengagement) within recess 436 of waveguide 430 for securing transducerassembly 453 of TAG 420 and waveguide 430 to one another. Further, inthe engaged position, proximal surface 438 of collar 434 of taperedproximal portion 432 of waveguide 430 is configured to abut distalsurface 466 of transducer assembly 453 of TAG 420.

Similarly as discussed above with respect to ultrasonic instrument 10(FIGS. 1-3), in order to ensure proper functionality of ultrasonicinstrument 400 and in order to maintain the engagement between waveguide430 and TAG 420 during use, it is important to ensure that waveguide 430and TAG 420 are properly and sufficiently secured to one another.Accordingly, various different latch mechanisms for securing thewaveguide and TAG of an ultrasonic instrument, e.g., ultrasonicinstrument 400, are provided, each of which will be described in detailin turn below.

Referring now to FIGS. 10A-10C and 11, one embodiment of a latchmechanism 500 configured for use with ultrasonic instrument 400 forengaging waveguide 430 and transducer assembly 453 of TAG 420 to oneanother is shown. Latch mechanism 500 generally includes a crank arm 510that is pivotably coupled to transducer assembly 453, and a cylindricalsleeve 520 pivotably coupled to crank arm 510 on either side ofcylindrical sleeve 520 via a pair of linkages 530. Crank arm 510includes a proximal segment 512, an intermediate segment 514, and adistal segment 516. Proximal and distal segments 512, 516, respectively,are angled relative to intermediate segment 514 to facilitate locking oflatch mechanism 500, as will be described in greater detail below.Proximal segment 512 includes a pair of spaced-apart portions configuredto receive transducer assembly 453 therebetween to pivotably couplecrank arm 510 to transducer assembly 453 on either side thereof via apair of opposed pivot pins 513. Distal segment 516 of crank arm 510 ispivotably coupled to first ends 532 of opposed linkages 530 via pivotpin 517. More specifically, linkages 530 are disposed on either side ofdistal segment 516 of crank arm 510 with pivot pin 517 extendingtherebetween to pivotably couple linkages 530 and distal segment 516 ofcrank arm 510 to one another. Second ends 534 of linkages 530, in turn,are pivotably coupled to sleeve 520 on either side thereof via a pair ofpivot pins 536. Sleeve 520 defines a generally cylindrical configurationhaving a lumen 522 extending longitudinally therethrough. Pivot pins 536are disposed on either side of sleeve 520 but do not extendsubstantially through sleeve 520 so at to not interfere with lumen 522.

With continued reference to FIGS. 10A-10C and 11, lumen 522 of sleeve520 defines a diameter sufficiently large to permit insertion ofwaveguide 30 therethrough but sufficiently small so as to inhibitpassage of proximal collar 434 of waveguide 430 therethrough. Due tothis configuration, when latch mechanism 500 is moved to the lockedposition, as will be described in greater detail below, proximal collar434 is retained in position between sleeve 520 and transducer assembly453, thus securing waveguide 430 and transducer assembly 453 of TAG 420to one another.

Referring still to FIGS. 10A-10C and 11, the engagement of waveguide 430and transducer assembly 453 of TAG 420 to one another using latchmechanism 500 is described. TAG 420 may be secured to handle assembly412 of ultrasonic instrument 400 prior to, simultaneously with, or afterengagement of transducer assembly 453 of TAG 420 and waveguide 430 toone another via any suitable mechanism, e.g., snap-fitting or othersuitable latch mechanisms. With initial reference to FIG. 10A, in orderto engage waveguide 430 and transducer assembly 453 to one another, thedistal end of waveguide 430 is inserted distally through lumen 522 ofsleeve 520 and is advanced therethrough until proximal collar 434 ofwaveguide 430 substantially approximates, or abuts proximal end 524 ofsleeve 520. At this point, crank arm 510 remains in an unlockedposition, wherein crank arm 510 extends upwardly from transducerassembly 453 such that sleeve 520 and waveguide 430 are generallyoffset-above transducer assembly 453, as shown in FIG. 10A.

In order to transition latch mechanism 500 to the locked position tosecure transducer assembly 453 and waveguide 430 to one another, withwaveguide 430 extending through lumen 522 of sleeve 520, crank arm 510is moved downwardly, as shown in FIG. 10B, such that crank arm 510 ispivoted about pivot pins 513 relative to transducer assembly 453 in thedirection of arrow “B” from the unlocked position toward the lockedposition. As crank arm 510 is pivoted in the direction of arrow “B,”waveguide 430 is moved toward alignment with transducer assembly 453 andlongitudinal axis “X-X” thereof. More specifically, as crank arm 510 ispivoted toward the locked position, recess 436 defined within proximalportion 432 of waveguide 430 is moved toward alignment with horn 464 oftransducer assembly 453 of TAG 420, which is centered about longitudinalaxis “X-X.”

During movement of crank arm 510 from the unlocked position towards thelocked position, linkages 530 and sleeve 520 are also pivoted aboutrespective pivot pins 536, 517 to facilitate alignment of waveguide 430and transducer assembly 453 with one another and to bring proximalcollar 434 of proximal portion 423 of waveguide 430 into approximationwith distal surface 466 of transducer assembly 453. More specifically,as crank arm 510 is pivoted towards the locked position, linkages 530are pivoted about pivot pins 536 in the direction of arrow “C” such thatsecond ends 534 of linkages 530 are oriented proximally of first ends532 thereof. In other words, linkages 530 are pivoted about pivot pins536 in the direction of arrow “C” such that linkages 530 extendproximally from distal segment 516 of crank arm 510 towards transducerassembly 453. Thus, as crank arm 510 is moved toward the lockedposition, waveguide 430 is moved into alignment with and intoapproximation with transducer assembly 453.

As crank arm 510 is moved further towards the locked position, proximalportion 432 of waveguide 430 is moved further towards alignment withtransducer assembly 453 and is approximated further relative totransducer assembly 453 such that horn 464 of transducer assembly 453 isreceived within recess 436 defined within proximal portion 432 ofwaveguide 430 and such that proximal collar 434 of waveguide 430 abutsdistal surface 466 of transducer assembly 453. When the locked positionhas been achieved, as shown in FIG. 10C, sleeve 520 retains proximalcollar 434 in abutting relation relative to distal surface 466 oftransducer assembly 453 such that horn 464 of transducer assembly 453 isretained within recess 436 defined within proximal portion 432 ofwaveguide 430 in friction-fit engagement therewith, thus securingwaveguide 430 and transducer assembly 453 to one another.

Latch mechanism 500, waveguide 430, and transducer assembly 453 may beconfigured such that, in the locked position, the engagement, interfaceor transition point, e.g., the point where the standing ultrasonic waveis transmitted from transducer assembly 453 to waveguide 430, is locatedat a displacement node, e.g., a point of minimal, or zero displacement.As a result, the energy lost through sleeve 520 is minimized. However,when the transition point is positioned at a displacement node, amaximum force, e.g., the nodal force, urges transducer assembly 453 andwaveguide 430 apart from one another. Thus, latch mechanism 500, in suchembodiments, is further configured so as to provide sufficient lockingforce to overcome the nodal force and retain transducer assembly 453 andwaveguide 430 in engagement with one another.

In this locked position, as shown in FIGS. 10C and 11, pivot pins 513and 517 are substantially aligned with one another and with respect tolongitudinal axis “X-X,” while pivot pins 536 are offset above pivotpins 513 and 517 and longitudinal axis “X-X.” This configuration isachievable due to the angling of proximal and distal segments 512, 516,respectively, of crank arm 510 relative to intermediate segment 514thereof. Further, this position corresponds to an over-center latchedposition, thus maintaining the engagement between waveguide 430 andtransducer assembly 453. With waveguide 430 and transducer assembly 453sufficiently engaged to one another in this locked position, ultrasonicinstrument 400 may be used to surgically treat tissue, similarly asdescribed above with respect to ultrasonic instrument 10 (FIGS. 1-3).

In order to unlock crank arm 510, i.e., in order to disengage waveguide430 and transducer assembly 453 from one another, intermediate segment514 (or any other suitable portion of crank arm 510) is grasped androtated about pivot pins 513 in the opposite direction of arrow “B” withsufficient force to overcome the over-center latched condition of pivotpins 536 relative to pivot pins 513 and 517. More particularly, uponrotation of crank arm 510, pivot pin 517 is translated upwardly relativeto pivot pins 536 until pivot pins 536 are no longer disposed abovepivot pins 513 and 517, i.e., such that pivot pints 536 are no longerdisposed in the over-center latched position. At this point, crank arm510 may be rotated further about pivot pins 513 to translate sleeve 520away from transducer assembly 453 and ultimately such that horn 464 oftransducer assembly 453 is withdrawn from recess 436 defined withinproximal portion 432 of waveguide 430. Thereafter, waveguide 430 can beremoved from sleeve 520.

As can be appreciated, the above-describe latch mechanism 500 providesefficient and effective latching and unlatching of waveguide 430 andtransducer assembly 453 to one another, thus facilitating both theassembly and disassembly of ultrasonic instrument 400 while alsosufficiently securing waveguide 430 and transducer assembly 453 to oneanother for use of ultrasonic instrument 400. Latch mechanism 500, insome embodiments, may further incorporate lockable cam member-cam slotengagements (not shown) configured to provide a desired compressionforce to lock transducer assembly 453 and waveguide 430 in engagementwith one another. Cam member-cam slot engagements (not shown) maysimilarly be incorporated into any of the other embodiments describedherein, for similar purposes.

Turning now to FIGS. 12A-14, another embodiment of a latch mechanism 700configured for use with an ultrasonic instrument 600 for engagingwaveguide 630 and TAG 620 to one another is shown. Ultrasonic instrument600 is similar to ultrasonic instrument 400 (FIG. 9) except for thedifferences specifically discussed hereinbelow. In particular,transducer assembly 653 of TAG 620 includes a distal collar 654 disposedabout the distal end 655 thereof.

Latch mechanism 700 generally includes a crank arm 710 pivotably coupledto waveguide 630 via pivot pins 713 and a semi-cylindrical sleeve, orcuff 720 pivotably coupled to crank arm 710 via a pair of linkages 730.Crank arm 710 includes a distal segment 712 and a proximal segment 716that are interconnected by and angled relative to an intermediatesegment 714. Proximal segment 716 of crank arm 710 is pivotable coupledto a pair of linkages 730 at first ends 732 thereof. More specifically,first ends 732 of linkages 730 are disposed on either side of proximalsegment 716 and are pivotably coupled thereto via a pivot pin 717extending therebetween. Cuff 720 includes a pair of opposed apertures722 defined therethrough. Second ends 734 of linkages 730 are pivotablycoupled to cuff 720 on either side thereof via pivot pins 736 extendingthrough apertures 722. Pivot pins 736 are disposed on either side ofcuff 720 but do not extend substantially through cuff 720. Distalsegment 712 of crank arm 710 defines a bifurcated configuration and ispivotably coupled to waveguide 630 on each side thereof via pivot pins713.

With continued reference to FIGS. 12A-14, cuff 720 defines an arcuaterecessed, or interior portion 724 that has a diameter sufficiently largeto at least partially surround body portion 656 of transducer assembly653, but sufficiently small so as to inhibit passage of cuff 720 beyonddistal collar 654 of transducer assembly 653. As such, when latchmechanism 700 is moved to the locked position, as will be described ingreater detail below, distal collar 654 of transducer assembly 653 isretained in position between cuff 720 and waveguide 630, thus securingwaveguide 630 and transducer assembly 653 to one another.

Referring still to FIGS. 12A-14, the engagement of waveguide 630 andtransducer assembly 653 of TAG 620 to one another using latch mechanism700 is described. Initially, with crank arm 710 disposed in the unlockedposition (FIG. 12A), waveguide 630 is translated into approximation withtransducer assembly 653 such that recess 636 defined within proximalportion 632 of waveguide 630 is positioned adjacent horn 668 oftransducer assembly 653 and such that cuff 720 is disposed adjacent bodyportion 656 of transducer assembly 653. Thereafter, cuff 720 istranslated towards body portion 656 of transducer assembly 653, e.g.,via rotation of crank arm about pivot pins 713 in the direction of arrow“D,” until cuff 720 is disposed about body portion 656 of transducerassembly 653, i.e., until body portion 656 of transducer assembly 653 isreceived within interior portion 724 of cuff 720. Cuff 720 is configuredto maintain the engagement of cuff 720 about body portion 656 oftransducer assembly 653. In particular, cuff 720 may be formed at leastpartially from a resiliently flexible material and interior portion 724thereof may define a diameter similar to that of body portion 656 oftransducer assembly 653 such that cuff 720 is flexed outwardly toreceive body portion 656 therein and is thus retained in engagementabout body portion 656 of transducer assembly 653 via the resilient biasof cuff 720. Alternatively, cuff 720 may be retained in engagement aboutbody portion 656 of transducer assembly 653 in any other suitablefashion, e.g., via friction-fitting.

With cuff 720 disposed about body portion 656 of transducer assembly653, crank arm 710, as shown in FIGS. 12A-12B, is rotated further in thedirection of arrow “D” such that crank arm 710 is pivoted about pivotpins 713 relative to waveguide 630 in the direction of arrow “D” fromthe unlocked position toward the locked position. As crank arm 710 ispivoted in the direction of arrow “D,” linkages 730 and cuff 720 arepivoted about pivot pins 717, 736, respectively, to align waveguide 630and transducer assembly 653 with one another and to bring proximalportion 632 of waveguide 630 into further approximation with distalcollar 654 of transducer assembly 653. More specifically, crank arm 710is pivoted in the direction of arrow “D” such that cuff 720 is pivotedin the direction of arrow “E,” thus effecting relative translation ofhorn 668 of transducer assembly 653 into recess 636 defined withinproximal portion 632 of waveguide 630 and relative translation of distalcollar 654 of body portion 656 of transducer assembly 653 into abutmentwith the proximal end of waveguide 630. When this locked position hasbeen achieved, as shown in FIGS. 12B and 14, cuff 720 retains distalcollar 654 in abutting relation relative to the proximal end ofwaveguide 630 such that horn 668 of transducer assembly 653 is retainedwithin recess 636 defined within proximal portion 632 of waveguide 630,thus securing waveguide 630 and transducer assembly 653 to one another.

In this locked position, as shown in FIGS. 12B and 14 and similarly asdescribed above with respect to latch mechanism 500 (FIGS. 10A-11),pivot pins 713, 717 are substantially aligned with one another and withrespect to longitudinal axis “X-X,” while pivot pins 736 are offsetabove pivot pins 713, 717 and longitudinal axis “X-X” to define anover-center latch configuration. This over-center latch configurationmaintains the engagement between waveguide 730 and transducer assembly753. With waveguide 730 and transducer assembly 753 sufficiently engagedto one another in this locked position, ultrasonic instrument 700 may beused to surgically treat tissue, similarly as described above withrespect to ultrasonic instrument 10 (FIGS. 1-3).

Latch mechanism 700, waveguide 630, and transducer assembly 653 may befurther configured such that, in the locked position, pivot pins 713 arelocated at a displacement node (where there is minimized displacementand maximized force) and such that the engagement, interface ortransition point between horn 668 of transducer assembly 653 andwaveguide 630 is located at a displacement anti-node (where there ismaximum displacement and minimum force). With the interface ortransition point between horn 668 of transducer assembly 653 andwaveguide 630 at an anti-node, minimal forces urge transducer assembly653 and waveguide assembly 630 apart from one another and, thus, arelatively smaller engagement force therebetween is required to maintainthe engagement of transducer assembly 653 and waveguide assembly 630 toone another.

In order to unlock crank arm 710, i.e., in order to disengage waveguide630 and transducer assembly 653 from one another, intermediate segment714 (or any other suitable portion of crank arm 710) is grasped androtated about pivot pins 713 in the opposite direction of arrow “D” withsufficient force to overcome the over-center latched condition of pivotpins 736 relative to pivot pins 713, 717. Initially, the rotation ofcrank arm 710 causes rotation of linkages 730 such that pivot pins 736are no longer disposed above pivot pins 713, 717. At this point, crankarm 710 may be rotated further about pivot pins 713 such that waveguide630 is translated away from cuff 720 and, ultimately, such that cuff 720is disengaged from body portion 656 of transducer assembly 453, therebyfully disengaging waveguide 630 and transducer assembly 653 from oneanother.

Turning now to FIGS. 15-16, another embodiment of a latch mechanism 900configured for use with an ultrasonic instrument 800 for engaging awaveguide 830 and a transducer assembly 853 of a TAG 820 to one anotheris shown. Ultrasonic instrument 800 is similar to those ultrasonicinstruments described above except for the differences specificallydiscussed hereinbelow.

Latch mechanism 900 includes a lever 910 pivotably coupled to waveguide830 via a pair of pivot pins 920. Lever 910 includes a handle portion912, an intermediate portion 914, and a transducer-engaging portion 916.Handle portion 912 of latch mechanism 900 extends from first end 922 ofintermediate portion 914 and may be ergonomically configured or may beotherwise configured to facilitate the grasping and/or rotation of lever910. Intermediate portion 914 defines a bifurcated configuration suchthat intermediate portion 914 is positionable about proximal portion 832of waveguide 830 on either side thereof. Intermediate portion 914 ispivotably coupled to proximal portion 832 of waveguide 830 on opposedsides thereof via pivot pins 920. As such, pivot pins 920 need notextend substantially through, or interfere with proximal portion 832 ofwaveguide 830. Transducer-engaging portion 916 extends from second end924 of intermediate portion 914 and likewise defines a bifurcatedconfiguration. Free ends 928 of the bifurcated transducer-engagingportion 916 each define a hook member 926. As will be described ingreater detail below, lever 910 is selectively pivotable to engage hookmembers 926 with opposed knobs 856, which extend outwardly from eitherside of body portion 854 of transducer assembly 853, to thereby securewaveguide 830 and transducer assembly 853 to one another. However, thereverse configuration is also contemplated, e.g., where lever 910 ispivotably coupled to transducer assembly 853 and knobs 856 are disposedon waveguide 830.

Continuing with reference to FIGS. 15-16, the engagement of waveguide830 and transducer assembly 853 to one another using latch mechanism 900is described. Initially, waveguide 830 is inserted through a distalopening formed within handle assembly 812 of ultrasonic instrument 800such that proximal portion 832 of waveguide 830 is disposed withinhandle assembly 812, while the remainder of waveguide 830 extendsdistally through shaft 814 of ultrasonic instrument 800. Alternatively,waveguide 830 may be pre-assembled, i.e., waveguide 830 may be coupledto handle assembly 812 during manufacture. Next, TAG 820 is insertedinto recess 850 formed within handle assembly 812 of ultrasonicinstrument 800 and is approximated relative to proximal portion 832 ofwaveguide 830 such that horn 858 is inserted into recess 834 and suchthat distal surface 862 of transducer assembly 853 is disposed in closeapproximation, or in abutting relation with proximal surface 836 ofwaveguide 830. TAG 820 may be configured to engage handle assembly 812in any suitable fashion, e.g., releasable snap-fit engagement. At thispoint, lever 910 remains disposed in an unlocked position, wherein hookmembers 926 are disengaged from opposed knobs 856.

In order to secure waveguide 830 and transducer assembly 853 to oneanother, lever 910 is rotated above pivot pins 920 in the direction ofarrow “F” such that hook members 926 are moved towards opposed knobs856. Lever 910 is rotated further in the direction of arrow “F” untilopposed knobs 856 are engaged within hook members 926, as shown in FIG.16. In this locked position, hook members 926 engage knobs 856 to retainwaveguide 830 and transducer assembly 853 in substantially fixedposition relative to one another and in alignment with longitudinal axis“X-X.” Further, hook members 926 may include resilient features,protrusions, or may define other configurations suitable for securelyretaining knobs 856 therein once hook members 926 are engaged aboutknobs 856. With waveguide 830 and transducer assembly 853 sufficientlyengaged to one another in this locked position, ultrasonic instrument800 may be used to surgically treat tissue, similarly as described abovewith respect to ultrasonic instrument 10 (FIGS. 1-3).

Latch mechanism 900, waveguide 830, and transducer assembly 853 may befurther configured such that, in the locked position, pivot pins 920 arelocated at a displacement node (where there is minimized displacementand maximized force) and such that the engagement, interface ortransition point between horn 858 of transducer assembly 853 andwaveguide 830 is located at a displacement anti-node (where there ismaximum displacement and minimum force). With the engagement betweenhorn 858 of transducer assembly 853 and waveguide 830 at an anti-node,minimal forces urge transducer assembly 853 and waveguide assembly 830apart from one another and, thus, a relatively smaller engagement forcetherebetween is required to maintain the engagement of transducerassembly 853 and waveguide assembly 830 to one another.

In order to unlock, or disengage waveguide 830 and transducer assembly853, lever 910 is pivoted in a direction opposite of arrow “F” such thathook members 926 of waveguide 830 are disengaged from and moved apartfrom knobs 856 of transducer assembly 853. Thereafter, with waveguide830 and transducer assembly 853 disengaged from one another, TAG 820 canbe removed from handle assembly 812 of ultrasonic instrument 800.

Turning now to FIGS. 17A-18B, another embodiment of a latch mechanism1100 for engaging a waveguide 1030 and transducer assembly 1053 of anultrasonic instrument 1000 to one another is shown. Ultrasonicinstrument 1000 is similar to the previous ultrasonic instrumentsdescribed herein, although latch mechanism 1100 may be also configuredfor use with any suitable ultrasonic instrument for engaging thewaveguide and transducer assembly thereof to one another. Accordingly,only those features of ultrasonic instrument 1000 that are necessary tofacilitate the understanding of latch mechanism 1100 are describedhereinbelow. In particular, proximal portion 1032 of waveguide 1030includes a longitudinal recess 1036 defined therein and a transverselumen 1038 extending therethrough that is substantially perpendicularrelative to recess 1036. Transverse lumen 1038 is defined betweenproximal surface 1042 of proximal portion 1032 of waveguide 1030 andproximal hub 1044 of waveguide 1030. Transducer assembly 1053, on theother hand, includes a body portion 1054 having a distal end including areduced-diameter intermediate segment 1056 extending therefrom and adistal stop member 1058 disposed at a distal end of reduced-diameterintermediate segment 1056. As will be described in detail below, thedistal end of transducer assembly 1053 is insertable into longitudinalrecess 1036 of waveguide 1030 and is selectively securable therein viamanipulation of latch mechanism 1100 from an unlocked position (FIGS.17A-17B) to a locked position (FIGS. 18A-18B).

Continuing with reference to FIGS. 17A-17B, latch mechanism 1100generally includes a pair of pushers 1110, 1120 disposed on either sideof waveguide 1030 and an angled chuck 1130 disposed between pushers1110, 1120. More specifically, latch mechanism 1100 includes a lockpusher 1110 that is selectively depressible to lock latch mechanism1100, i.e., to lock waveguide 1030 and transducer assembly 1053 inengagement with one another, and an unlock pusher 1120 that isselectively depressible to unlock latch mechanism 1100, i.e., to unlockwaveguide 1030 and transducer assembly 1053 from one another. Angledchuck 1130 defines an angled, or tapered configuration wherein chuck1130 defines a relatively larger width “W” at first end 1132 thereof,which is positioned adjacent lock pusher 1110, and tapers to arelatively smaller width “w” at second end 1134 thereof, which ispositioned adjacent unlock pusher 1120 (see FIGS. 17A and 18A). Angledchuck 1130 also defines a bifurcated configuration at second end 1134thereof including a pair of legs 1136, 1138 that are spaced-apart andangled-apart from one another to define a generally A-shaped slot 1140therebetween (see FIGS. 17B and 18B). That is, due to the angled-apartconfiguration of legs 1136, 1138 the gap distance between legs 1136,1138, which defines A-shaped slot 1140, is at a minimum gap distance “g”at the closed end 1142 thereof and is at a maximum gap distance “G” atthe open end 1144 thereof.

Referring still to FIGS. 17A-18B, the engagement of waveguide 1030 andtransducer assembly 1053 to one another using latch mechanism 1100 isdescribed. Initially, latch mechanism 1100 is disposed in the unlockedposition, shown in FIGS. 17A-17B, wherein lock pusher 1110 extends fromhandle assembly 1012 of ultrasonic instrument 100 and wherein unlockpusher 1120 is disposed within handle assembly 1012 such that chuck 1130is disposed in the unlock position. More specifically, in the unlockedposition, only a portion of chuck 1130, e.g., the portion adjacentsecond end 1134 of chuck 1130, extends through transverse lumen 1038 ofproximal portion 1032 of waveguide 1030. As such, with only second end1134 of chuck 1130 disposed within transverse lumen 1038, the minimuminternal diameter of longitudinal recess 1036, which is defined by theportion of slot 1140 of chuck 1130 disposed therein, approximates gapdistance “G,” the maximum gap distance defining A-shaped slot 1140between legs 1136, 1138 of chuck 1130. In this position, whereinlongitudinal recess 1036 defines a minimum internal diameterapproximating gap distance “G,” distal stop member 1058,reduced-diameter intermediate segment 1056, and at least a portion ofbody portion 1054 of transducer assembly 1053 are insertable into recess1036 of waveguide 1030 (see FIG. 17B). In other words, with latchmechanism 1100 disposed in the unlocked position, transducer assembly1053 may be inserted into and/or removed from proximal portion 1032 ofwaveguide 1030 to engage/disengage transducer assembly 1053 andwaveguide 1030.

With latch mechanism 1100 disposed in the unlocked position, asmentioned above, transducer assembly 1053 is inserted into recess 1036of waveguide 1030 such that distal stop member 1058 is positionedadjacent proximal surface 1042, reduced-diameter intermediate segment1056 is positioned adjacent transverse lumen 1038, and at least aportion of body portion 1054 is positioned adjacent proximal hub 1044.Once transducer assembly 1053 is disposed within recess 1036 ofwaveguide 1030 in this position, latch mechanism 1100 may betransitioned from the unlocked position to the locked position to lock,or secure transducer assembly 1053 and waveguide 1030 in engagement withone another.

In order to transition latch mechanism 1100 from the unlocked positionto the locked position, lock pusher 1110 is depressed, or pushedinwardly into handle assembly 1012 of ultrasonic instrument 1000 suchthat chuck 1130 is urged through transverse lumen 1038 from the unlockedposition towards the locked position. As chuck 1130 is urged towards thelocked position, second end 1134 of chuck 1130 urges unlock pusher 1120to extend from handle assembly 1012 of ultrasonic instrument 1000 tofacilitate unlocking of latch mechanism 1100, as will be describedbelow. Further, pusher 1110 and/or pusher 1120 may be biased apart fromchuck 1130 so as not to contact chuck 1130 other than while beingdepressed to urge chuck 1130 between the locked and unlocked positions.Such a configuration is advantageous in that, since pushers 1110, 1120are spaced-apart from chuck 1130 during use, ultrasonic energytransmitted from transducer assembly 1053 along waveguide 103 is nottransmitted to pushers 1110, 1120.

As best shown in FIGS. 18A-18B, depression of lock pusher 1110, asmentioned above, urges chuck 1130 through transverse lumen 1038 towardsthe locked position. More specifically, as chuck 1130 is translatedfurther through transverse lumen 1038, an intermediate portion, e.g.,the portion between first and second ends 1132, 1134, respectively, ofchuck 1130 is disposed within transverse lumen 1038 of proximal portion1032 of waveguide 1030. As such, with this intermediate portion of chuck1130 disposed within transverse lumen 1038, the minimum internaldiameter of longitudinal recess 1036, which is defined by the portion ofslot 1140 of chuck 1130 disposed therein, approximates gap distance “g,”the minimum gap distance defining A-shaped slot 1140 between legs 1136,1138 of chuck 1130. In this position, wherein longitudinal recess 1036defines a minimum internal diameter approximating gap distance “g,”distal stop member 1058 is inhibited from being translated proximallythrough recess 1036 (see FIG. 18B), i.e., transducer assembly 1053 isinhibited from being withdrawn from waveguide 1030. Further, due to theangled configuration of chuck 1130 (wherein chuck 1130 defines a greaterwidth “W” at first end 1132 thereof as compared to width “w” at secondend 1134 thereof), as chuck 1130 is moved to the locked position, thewidth of the portion of chuck 1130 disposed through transverse lumen1038 is increased. Thus, as chuck 1130 is urged further towards thelocked position, the width of the portion of chuck 1130 disposed throughtransverse lumen 1038 eventually approximates width “W,” at which pointchuck 1130 is wedged between proximal hub 1044 of waveguide 1030 anddistal stop member 1058 of transducer assembly 1053 to secure transducerassembly 1053 and waveguide 1030 to one another, inhibiting relativemovement therebetween. This position corresponds to the locked positionof latch mechanism 1100.

Latch mechanism 1100, waveguide 1030, and transducer assembly 1053 maybe further configured such that, in the locked position, chuck 1130(which constitutes the engagement, interface or transition point betweenwaveguide 1030 and transducer assembly 1053) is located at adisplacement anti-node, where there is maximum displacement and minimumforce, such that minimal forces urge transducer assembly 1053 andwaveguide assembly 1030 apart from one another and, thus, such that arelatively smaller engagement force therebetween is required to maintainthe engagement of transducer assembly 1053 and waveguide assembly 1030to one another.

With waveguide 1030 and transducer assembly 1053 sufficiently engaged toone another in this locked position, ultrasonic instrument 1000 may beused to surgically treat tissue, similarly as described above withrespect to ultrasonic instrument 10 (FIGS. 1-3). At the completion ofthe procedure(s), waveguide 1030 and transducer assembly 1053 can bedisengaged from one another via depressing pusher 1120 into handleassembly 1012 of ultrasonic instrument 1000 such that chuck 1130 isurged back towards the unlocked position (FIGS. 17A-17B). Thereafter,transducer assembly 1053 may be withdrawn from recess 1036 of waveguide1030 to completely disengage transducer assembly 1053 and waveguide 1030from one another.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of particular embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of theclaims appended hereto.

What is claimed is:
 1. An ultrasonic surgical instrument, comprising: atransducer assembly configured to supply ultrasonic energy, thetransducer assembly including a distal engagement member; a waveguidedefining a longitudinal axis and having a proximal engagement memberconfigured to threadingly engage the distal engagement member of thetransducer assembly, the waveguide configured to transmit the ultrasonicenergy therealong from the proximal engagement member to a distal endthereof for treating tissue; and a torque member coupled to thetransducer assembly and disposed about the longitudinal axis, the torquemember selectively rotatable about the longitudinal axis and relative tothe waveguide to threadingly engage the transducer assembly and thewaveguide, the torque member including a plurality of fingers pivotablycoupled thereto and movable between a closed position, wherein thefingers are disposed in close proximity to one another and relative tothe longitudinal axis, and a open position, wherein each finger extendsradially-outwardly from the longitudinal axis in substantiallyperpendicular orientation relative to the longitudinal axis to define amoment arm configured to facilitate threading engagement of thetransducer assembly and the waveguide.
 2. The ultrasonic surgicalinstrument according to claim 1, further comprising a tool assemblydisposed at the distal end of the waveguide, the tool assembly includinga blade coupled to the waveguide and a clamp member movable relative tothe blade from an open position to a clamped position for clampingtissue between the clamp member and the blade.
 3. The ultrasonicsurgical instrument according to claim 1, further comprising atransducer and generator assembly including the transducer assembly anda generator coupled to the transducer assembly.
 4. The ultrasonicsurgical instrument according to claim 3, wherein the transducer andgenerator assembly rotatably supports the transducer assembly thereon.5. The ultrasonic surgical instrument according to claim 3, wherein thetransducer and generator assembly is releasably engagable with a handleassembly of the ultrasonic surgical instrument.
 6. The ultrasonicsurgical instrument according to claim 1, wherein the proximalengagement member of the waveguide includes a threaded extensionconfigured for engagement within a threaded bore defined within thedistal engagement member of the transducer assembly.
 7. The ultrasonicsurgical instrument according to claim 1, wherein the fingers of thetorque member are stable in each of the open and closed positions.
 8. Anultrasonic surgical instrument, comprising: a transducer assemblyconfigured to supply ultrasonic energy, the transducer assemblyincluding a distal engagement member; a waveguide defining alongitudinal axis and having a proximal engagement member configured toengage the distal engagement member of the transducer assembly, thewaveguide configured to transmit the ultrasonic energy therealong fromthe proximal engagement member to a distal end thereof for treatingtissue; and a latch mechanism configured to releasably engage thetransducer assembly and the waveguide to one another, the latchmechanism including: a crank arm having a first end and a second end,the crank arm pivotably coupled to one of the transducer assembly andthe waveguide at the first end thereof via a first pivot; a linkagepivotably coupled to the second end of the crank arm at a first end ofthe linkage via a second pivot; and a sleeve member pivotably coupled tothe linkage at a second end of the linkage via a third pivot, the sleevemember at least partially positionable about the other of the transducerassembly and the waveguide; wherein, the crank arm is selectivelypivotable about the first pivot between an unlocked position, whereinthe distal engagement member of the transducer assembly and the proximalengagement member of the waveguide are spaced-apart relative to oneanother, and a locked position, wherein the first and second pivots arealigned with one another and the longitudinal axis and wherein the thirdpivot is disposed in an over-center position relative to the first andsecond pivots and the longitudinal axis such that the sleeve membermaintains the distal engagement member of the transducer assembly andthe proximal engagement member of the waveguide in engagement with oneanother.
 9. The ultrasonic surgical instrument according to claim 8,wherein the crank arm is pivotably coupled to the transducer assembly atthe first end thereof and wherein the waveguide is at least partiallyinsertable through a lumen defined through sleeve member.
 10. Theultrasonic surgical instrument according to claim 9, wherein thewaveguide includes a proximal collar, the proximal collar inhibited frompassing through the sleeve member such that, in the locked position, thesleeve member abuts the proximal collar to maintain the distalengagement member of the transducer assembly and the proximal engagementmember of the waveguide in engagement with one another.
 11. Theultrasonic surgical instrument according to claim 9, wherein, in thelocked position, the proximal engagement member of the waveguide engagesthe distal engagement member of the transducer assembly at adisplacement node.
 12. The ultrasonic surgical instrument according toclaim 8, wherein the crank arm is pivotably coupled to the waveguide atthe first end thereof and wherein the sleeve member is positionableabout at least a portion of the transducer assembly.
 13. The ultrasonicsurgical instrument according to claim 12, wherein the transducerassembly includes a distal collar and wherein, in the locked position,the sleeve member abuts the distal collar to maintain the distalengagement member of the transducer assembly and the proximal engagementmember of the waveguide in engagement with one another.
 14. Theultrasonic surgical instrument according to claim 12, wherein, in thelocked position, the proximal engagement member of the waveguide engagesthe distal engagement member of the transducer assembly at adisplacement anti-node and wherein a pivot point between the crank armand the waveguide is located at a displacement node.
 15. An ultrasonicsurgical instrument, comprising: a transducer assembly configured tosupply ultrasonic energy, the transducer assembly including a distalstop member disposed at a distal end thereof; a waveguide including aproximal hub, the waveguide defining a longitudinal recess configured toreceive at least a portion of the transducer assembly therein and atransverse lumen extending therethrough in substantially parallelorientation relative to the longitudinal recess, the waveguideconfigured to transmit the ultrasonic energy therealong to a distal endthereof for treating tissue; and a latch mechanism configured toreleasably engage the transducer assembly and the waveguide to oneanother, the latch mechanism including: an angled chuck movably disposedwithin the transverse lumen, the angled chuck having a first enddefining a first width and a second end defining a second width smallerthan the first width, the angled chuck including a pair of spaced-apartlegs at the second end thereof defining a slot therebetween, the legsangled relative to one another such that the legs define a first gapdistance therebetween at a closed end thereof and a second gap distancetherebetween at an open end thereof that is greater than the first gapdistance, the angled chuck selectively movable between an unlockedposition, permitting insertion of the at least a portion of thetransducer assembly into the longitudinal recess and through the slot,and a locked position, wherein withdrawal of the distal stop memberthrough the slot is inhibited and wherein the angled chuck is wedgedbetween the distal stop member of the transducer assembly and theproximal hub of the waveguide to engage the transducer assembly andwaveguide to one another.
 16. The ultrasonic surgical instrumentaccording to claim 15, further comprising a lock pusher, the lock pusherpositioned adjacent the first end of the chuck and selectivelydepressible to move the chuck from the unlocked position to the lockedposition.
 17. The ultrasonic surgical instrument according to claim 15,further comprising an unlock pusher positioned adjacent the second endof the chuck and selectively depressible to move the chuck from thelocked position to the unlocked position.
 18. The ultrasonic surgicalinstrument according to claim 16, wherein, in the locked position, theangled chuck is located at a displacement anti-node.
 19. An ultrasonicsurgical instrument, comprising: a transducer assembly configured tosupply ultrasonic energy, the transducer assembly including a distalengagement member and a pair of opposed knobs extending outwardlytherefrom adjacent a distal end thereof; a waveguide having a proximalengagement member configured to engage the distal engagement member ofthe transducer assembly, the waveguide configured to transmit theultrasonic energy therealong from the proximal engagement member to adistal end thereof for treating tissue; and a latch mechanism configuredto releasably engage the transducer assembly and the waveguide to oneanother, the latch mechanism including: a lever including a handleportion, an intermediate portion, and an engaging portion, the leverpivotably coupled to the waveguide about the intermediate portionthereof, the handle portion extending from one end of the intermediateportion, the engaging portion extending from the other end of theintermediate portion, the engaging portion defining a bifurcatedconfiguration and including a pair of hook members, the handle portionselectively movable between an unlocked position and a locked positionto move the hook members into engagement with the knobs to engage thedistal engagement member of the transducer assembly and the proximalengagement member of the waveguide with one another.
 20. The ultrasonicsurgical instrument according to claim 19, wherein, in the lockedposition, the proximal engagement member of the waveguide engages thedistal engagement member of the transducer assembly at a displacementanti-node and wherein a pivot point between the lever and the waveguideis located at a displacement node.